Case report

A 24-year-old primigravida was referred to your antenatal unit at 34 weeks for further evaluation of a fetal abdominal mass. Her previous ultrasonographic examinations were normal. The mass was large, nonvascular, thin-walled, cystic structure with multiple irregular inner echogenic structures of the size 60x50x45 mm. The cyst was located in the left inferior quadrant of the abdomen. The gender of the fetus was feminine. We proposed the diagnosis of the ovarian cyst.

The size os the structure was decreasing during the rest of the pregnancy (36 weeks - 40x55 mm; 39 weeks - 24x22 mm). The neonate was delivered at 40 weeks with a normal postnatal adaptation. Four day after delivery the ultrasonographic examination found normal sized ovary of the neonate.

Images 1, 2: 34 weeks of pregnancy; Image 1 shows the parasagittal views of the fetal abdomen. The left side of the image shows the ovarian cyst anteriorly to the normal left kidney. The right side of the images shows normal right kidney of the fetus. Image 2 shows transverse scans through the fetal abdomen with the ovarian cyst localized in the left part of the abdomen.

Images 3, 4: 34 weeks; Images show detailed view at the ovarian cyst localized in the left inferior abdomen of the fetus.

Images 5, 6: 34 weeks; Image 5 shows the low transverse scan of the fetal pelvis with the urinary bladder in the middle (short course of uterine arteries are visible in color Doppler mode) and the ovarian cyst at the left side of the urinary bladder. Image 6 shows detailed view at the ovarian cyst localized in the left inferior abdomen of the fetus.

Images 7, 8: Images show decreasing size of the ovarian cyst during the 36th (Image 7) and 39th (Image 8) weeks of pregnancy.